Account management

Hi jking, 

It's possible that you set up the customer's delivery method to email.

Here's how you can check the setup: 

1. Click Customers from the left menu. 
2. Select the customer name and click on Edit at the top right corner. 
3. Click the Payment and billing tab. Set the Preferred delivery method to None.
4. Click Save.

I've included a screenshot below for reference. 

This should de-select the Send later or email option on your invoices by default.

I hope this gets you what you needed today. Don’t hesitate to post again with any questions. Have a great day!